1. Field of the Invention
The present invention relates to a computer system, and more specifically, to a computer system with vertically offset hard disk drives.
2. Description of the Prior Art
Due to the need for standardization and modularization, industry has drawn up standards that regulate specifications of network servers, including 1.75 inches as a standard height unit. A server conforming to this standard unit is called a 1U server. Because of this height regulation of servers, the heights of hard disk drives should also conform to the standard.
Prior art 1U servers can only accommodate standard 3.5-inch (width) hard disk drives since the height of the server is limited. Please refer to FIG. 1, which illustrates a prior art mobile rack with a single hard disk drive. The mobile rack carries a single hard disk drive and can be inserted into the prior art server. However, to meet the requirement of mass data processing, increasing the number of hard disk drives of a server has become an inevitable tendency, hence the 2U, 3U, and 4U server specifications to accommodate more hard disk drives have been developed. In these specifications, hard disk drives are vertically stacked inside a server. Another server design conforming to the 1U server specification has a plurality of hard disk drives installed in a juxtaposed manner. This server design includes a casing divided into four housing spaces by three partitions. Please refer to FIG. 2, which shows a design from U.S. Pat. No. 6,768,638 entitled “Server Contained Four Juxtaposed Hard Disk Drives” that improves the features of the partitions and uses a novel retrieval cradle such that the server can accommodate four juxtaposed hard disk drives in an inherent inner width of 17 inches. However, this design merely laterally improves the space utilization of a server by reducing the space needed by the partitions, contributing little improvement to overall space utilization.
A similar problem exists in notebook computers. To meet the requirement of portability, a notebook computer has similar restrictions as the above-described servers regarding space for a hard drive. The prior art notebook has space only for a single micro hard drive, which means there is room for improvement in notebook space utilization.